Answer:
A) that states had the constitutional right to secede from the United States
Explanation:
James Buchanan was the 15th president of USA. It was during his presidency that seven southern states seceded from the Union and brought the nation on the brink of civil war.
He was from Pennsylvania and began his career in Pennsylvania state's legislature. He later served in both the houses of the U.S congress.
Buchanan was a democrat and he morally opposed slavery while believing that it was supported by the US constitution.. He got elected to the White House in 1856.
He tried to maintain peace between the anti and pro slavery factions in the government.<u><em> In 1856 general election Buchanan supported the idea that slavery was an issue to be decide by the individual territories and states while his challenger John Fremont asserted that the federal government should bad slavery in all the territories.</em></u>
He did not seek reelection after his first term as president but he proposed that sates did not have the right to secede and he had no constitutional power to stop them. The slavery crisis was left for the Lincoln administration to resolve.